1 //===----------------------------------------------------------------------===//
2 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
3 // See https://llvm.org/LICENSE.txt for license information.
4 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
5 //
6 //===----------------------------------------------------------------------===//
7 
8 // UNSUPPORTED: c++03, c++11, c++14, c++17
9 // UNSUPPORTED: libcpp-has-no-incomplete-format
10 
11 // Tests whether a move only type can be formatted. This is required by
12 // P2418R2 "Add support for std::generator-like types to std::format"
13 
14 // <format>
15 
16 #include <format>
17 #include <cassert>
18 
19 #include "MoveOnly.h"
20 #include "make_string.h"
21 #include "test_macros.h"
22 
23 #ifndef TEST_HAS_NO_LOCALIZATION
24 #  include <locale>
25 #endif
26 
27 #define SV(S) MAKE_STRING_VIEW(CharT, S)
28 
29 template <class CharT>
30 struct std::formatter<MoveOnly, CharT> : std::formatter<int, CharT> {
31   // TODO FMT Make this a const member function after the base class has been adapted.
32   auto format(const MoveOnly& m, auto& ctx) -> decltype(ctx.out()) {
33     return std::formatter<int, CharT>::format(m.get(), ctx);
34   }
35 };
36 
37 template <class CharT>
38 static void test() {
39   MoveOnly m{10};
40   CharT buffer[10];
41 #ifndef TEST_HAS_NO_LOCALIZATION
42   std::locale loc;
43 #endif
44 
45   assert(std::format(SV("{}"), MoveOnly{}) == SV("1"));
46 
47   assert(std::format(SV("{}"), m) == SV("10"));
48   assert(m.get() == 10);
49 
50   assert(std::format(SV("{}"), std::move(m)) == SV("10"));
51   assert(m.get() == 10);
52 
53 #ifndef TEST_HAS_NO_LOCALIZATION
54   assert(std::format(loc, SV("{}"), MoveOnly{}) == SV("1"));
55 
56   assert(std::format(loc, SV("{}"), m) == SV("10"));
57   assert(m.get() == 10);
58 
59   assert(std::format(loc, SV("{}"), std::move(m)) == SV("10"));
60   assert(m.get() == 10);
61 #endif
62 
63   assert(std::format_to(buffer, SV("{}"), MoveOnly{}) == &buffer[1]);
64 
65   assert(std::format_to(buffer, SV("{}"), m) == &buffer[2]);
66   assert(m.get() == 10);
67 
68   assert(std::format_to(buffer, SV("{}"), std::move(m)) == &buffer[2]);
69   assert(m.get() == 10);
70 
71 #ifndef TEST_HAS_NO_LOCALIZATION
72   assert(std::format_to(buffer, loc, SV("{}"), MoveOnly{}) == &buffer[1]);
73 
74   assert(std::format_to(buffer, loc, SV("{}"), m) == &buffer[2]);
75   assert(m.get() == 10);
76 
77   assert(std::format_to(buffer, loc, SV("{}"), std::move(m)) == &buffer[2]);
78   assert(m.get() == 10);
79 #endif
80 
81   assert(std::format_to_n(buffer, 5, SV("{}"), MoveOnly{}).out == &buffer[1]);
82 
83   assert(std::format_to_n(buffer, 5, SV("{}"), m).out == &buffer[2]);
84   assert(m.get() == 10);
85 
86   assert(std::format_to_n(buffer, 5, SV("{}"), std::move(m)).out == &buffer[2]);
87   assert(m.get() == 10);
88 
89 #ifndef TEST_HAS_NO_LOCALIZATION
90   assert(std::format_to_n(buffer, 5, loc, SV("{}"), MoveOnly{}).out == &buffer[1]);
91 
92   assert(std::format_to_n(buffer, 5, loc, SV("{}"), m).out == &buffer[2]);
93   assert(m.get() == 10);
94 
95   assert(std::format_to_n(buffer, 5, loc, SV("{}"), std::move(m)).out == &buffer[2]);
96   assert(m.get() == 10);
97 #endif
98 
99   assert(std::formatted_size(SV("{}"), MoveOnly{}) == 1);
100 
101   assert(std::formatted_size(SV("{}"), m) == 2);
102   assert(m.get() == 10);
103 
104   assert(std::formatted_size(SV("{}"), std::move(m)) == 2);
105   assert(m.get() == 10);
106 
107 #ifndef TEST_HAS_NO_LOCALIZATION
108   assert(std::formatted_size(loc, SV("{}"), MoveOnly{}) == 1);
109 
110   assert(std::formatted_size(loc, SV("{}"), m) == 2);
111   assert(m.get() == 10);
112 
113   assert(std::formatted_size(loc, SV("{}"), std::move(m)) == 2);
114   assert(m.get() == 10);
115 #endif
116 }
117 
118 int main(int, char**) {
119   test<char>();
120 
121 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
122   test<wchar_t>();
123 #endif
124 
125   return 0;
126 }
127